Condensed Consolidated Statements of Shareholders' Equity (Unaudited) (Parentheticals) $ in Thousands	9 Months Ended
	Sep. 30, 2018 USD ($) $ / shares shares
Common Class A [Member]
Shares of treasury stock purchased (in shares)	169,568
Shares of common stock issued for the exercise of stock option (in shares)	380,958
Issuance of restricted common shares, net of forfeitures (in shares)	3,496
Settlement of restricted common shares and stock options in connection with recapitalization (in shares)	90,369
Settlement of class B common shares in connection with recapitalization, shares issued (in shares)	3,527,246
Dividends declared per common share (in dollars per share) | $ / shares	$ 0.44
Common Class B [Member]
Shares of treasury stock purchased (in shares)	3,677
Shares of common stock issued for the exercise of stock option (in shares)	9,296
Cash paid settlement of restricted common shares and stock options in connection with recapitalization | $	$ 3,271
Settlement of class B common shares in connection with recapitalization, shares exchanged (in shares)	3,527,246
Retirement of class B common shares in connection with recapitalization, shares retired (in shares)	4,328,552
Dividends declared per common share (in dollars per share) | $ / shares	$ 0.60
Settlement of class B common shares in connection with Recapitalization, cash exchanged | $	$ 69,099